Won't call on method in other class, Objective-C - ios

Question

I am trying to learn Objective-C for iOS. i am currently following the "coding together" on iTunesU. Although i have got stuck since i can't get my controller to call on a method from another class. Can't find what i am doing wrong and thought that StackOverflow might have the solution to it!
The method "flipCardAtIndex" is the one that isn't working. I have debugged using nslog and from the method "flipCard" i get an output. But when i put in the implementation for flipCardAtIndex i don't get anything.. So my guess is that it never calls it...
I have made the code a bit shorter so it is only the parts i think is important, this is controller:
#import "ViewController.h"
#import "PlayingCardDeck.h"
#import "CardMatchingGame.h"
#interface ViewController ()
#property (weak, nonatomic) IBOutlet UILabel *flipsLabel;
#property (nonatomic) int flipCount;
#property (weak, nonatomic) IBOutlet UILabel *scoreLabel;
#property (strong, nonatomic) IBOutletCollection(UIButton) NSArray *cardButtons;
#property (strong, nonatomic) CardMatchingGame *game;
#end
#implementation ViewController
- (CardMatchingGame *) game{
if (_game) _game = [[CardMatchingGame alloc] initWithCardCount:[self.cardButtons count]
usingDeck:[[PlayingCardDeck alloc] init]];
return _game;
}
- (IBAction)flipCard:(UIButton *)sender {
[self.game flipCardAtIndex:[self.cardButtons indexOfObject:sender]];
self.flipCount++;
[self updateUI];
}
And implementation:
- (void)flipCardAtIndex:(NSUInteger)index
{
NSLog(#"ALL YOUR BASE ARE BELONG TO US");
Card *card = [self cardAtIndex:index];
}

Answer 1

Fix?
- (CardMatchingGame *) game{
if (!_game) _game = [[CardMatchingGame alloc] initWithCardCount:[self.cardButtons count] usingDeck:[[PlayingCardDeck alloc] init]];
return _game;
}